Hearing aid



May 6,1941. 2,241,093

' HEARING AID Filed June 16, 1938 2' Sheets- Sheet 1 INVENTOR ATTORNEY Patented May 6, 1941 Hugo Lieber,

deceased, late of New York, N. Y., by

Dora Lieber, executrix, New York, N. Y assignor to Lieber Patents Corporation, a corporation of New York Application June 16, 1938, SerlaINo. 214,025

2 Claims.

This application is a continuation-in-part of the co-pending application, Serial No, .741,487, filed August 25, 1934, by Hugo Lieber, deceased.

This invention relates-to hearing aids, andit has among its objects an improved wearable micrcphone-amplifier hearing aid ,in which the microphone amplifier is arranged and. combined with the transmitter and receiver circuits to-permit quick' changeover from simplified operation with the receiver directly connected to the transmitter to amplified operation with the amplifier operatively connected between the receiver and amplifier, and vice versa, without changing the operative correlation of the cords interconnecting the transmitter and receiver with the other elements oi the hearing aid.

The foregoing and other objects of the invention will be best understood from the following description of exemplifications thereof, reference being had to the accompanying drawings wherein Fig. l is a diagrammatic view of a wearable hearing aid exemplifying the invention, as applied to a hearing aid using two receivers; and

Figs. 2' and 3 are views similar to Fig. 1 of such hearing aid as applied to a hearing aid utilizing one receiver.

Although the need for changing a wearable I hearing aid for amplified operation with the amplifier connected between the transmitter and receiver to simplifiedoperation, with a direct connection ofthe transmitter to the receiver was realized long ago, heretofore all such changes required a cumbersome interchange of the cord plug interconnections between the hearing aid elements.

The invention provides for a quick changeover of the connections by simple switch arrangement forming a permanent element or the hearing aid circuits.

An exemplification of the invention as applied to a wearable hearing aid equipped with an air conduction and bone-conduction receiver for supplying the user simultaneously with optimum sound reception over his air conduction path optimum sound reception over his bone conduction path is shown in Fig. 1.

It comprises a battery umt I, an amplifier unit 2, a transmitter unit 3, a telephone receiver 4 and a bone-conduction receiver 5 the transmitter and the two oscillators being connected to terminals provided on the amplifier by means of cords 6, l, 8, respectively. The battery is provided at its top with two terminal sleeves 9 and I0, one terminal sleeve 9 being, for instance, connected to the positive pole of the battery and the other terminal sleeve III to the negative pol of the battery.

The transmitter mlcrophoneunit 3 comprises a diaphragm shaped carbon electrode H and a cooperating chamber. carbon electrode l2. The two transmitter microphone electrodes are connected in series with the two cord leads 6 extending therefrom. The telephone receiver 4 has an actuating winding l4 and the bone receiver 5 has an actuating winding l5 connected in series-with the cord leads I and 8. The amplifier unit 2 has a substantially rectangular fiat housing .81 fitting the top of the battery unit. I and having mounted on the bottom wall two supply pin terminals l8 and |9..\mechanically and electrically. engaging.,the battery terminal sleeves 9, ill to. firmly hold-the amplifier unit on the top of the battery and permit comfortable wear of the combined unit concealed in the clothing of the user.

Within the housing are mounted--two.microphone amplifier units 2t, 22, of the type described in Reissue Patent 19,246, each amplifier unit comprising a microphone chamber electrode 23,-a

microphone diaphragm electrode 24, anda vibrator including an actuating winding 25 for imparting vibrations to. the microphone diaphragm 24 in accordance with the sound-frequency current oscillations traversing the .winding. Two threepole switches 3| are provided in the opposite wall.

sides of thev housing, each switch having three contact bridging members 32, 33, 34 actuated by a movable switch arm. 35. Bridging member 32 serves to establish a connection between the contact member 32a with contact 3% if the switch arm 35 is moved to its upper position, and with contact 320 if the arm is moved to the lower position. In a similar way, switching bridging contacts 83 and 34 serve to connect'contacts 33a. and 34a to contacts 331; and 330, 34b and 340, re-

spectively. I

There is also provided in the housing a rheostat unit 31 in which a movable contact member 38 slidably mounted'on a contact rod 39 is arranged to make and break contact with a resistor member 40 and a stationary contact member 4!. A second rheostat unit 43 provided within the housing comprises a movable contact member 44 slidply terminal l8 of the amplifier unit is connected through a conductor 41 extending within the housing to the stationary contact member M ,of' the rheostat 31. The negative supply terminal ,I 9 of the amplifier unit is similarly connected through two branches of a conductor 48 to the her.

terminals 34a lying opposite the bridging members 34 of the two switches 35. The microphone diaphragm 24 and one endof the winding 25 of each microphone are connected to the switch contacts 34b. The other end of the winding 25 of each microphone amplifier'unit is interconnected through a conductor 50 which in turn is also connected to the switch contacts 320. The microphone chamber electrodes 23 are connected through conductors 5| extending through the casing to the switch contacts 33b. One end of the resistor 40 of the rheostat unit 31 is connected through a conductor 53 with two switch contacts 32b. The sliding rod 45 of rheostat 43 is connected through conductor 54 to switch contacts 34c. One end of the rheostat unit 43 is connected through the conductor 55 to the two switch contacts 330. The arms 35 of the two switches 3i terminate in gripping portions projecting from the wall of the housing.

By pulling the switch arm 35 up,- each switch establishes a conducting connection between the contacts 32a, 33a, 34a and contacts 32b, 33b, 34b, respectively; and on pushing the switch arm 35 in, bridging members 32 and 34 establish conducting connections between the contacts 32a, 33a, 34a with the contacts 320, 33c, 34c respectively. The contacts 32a to 340 press resiliently against the adjacent surfaces of the contact arm 35 so as to positively establish and break the contact between the corresponding contact members depending on the position of the contact arm. The contact members 3221 and 33a of the switch associated with the amplifier unit 2| are connected to terminal pins 2la, Zlb secured to one side wall of the housing, and the corresponding contact members of the switch associated with the amplifier unit 22 are similarly connected to terminal pins 22a, 22b mounted on the opposite wall of the housing. The receiver cords] and 3 have suitable terminal sockets for engaging the terminal pins 2la, 2Ib, 22a, 22b, respectively. In the upper wall of the housing there are secured two terminal sleeves 31a, 31b for receiving terminal plugs 6a of the cord 6 leading from the transmitter microphone electrodes. In series with the leads I and 8 to the receiver windings are connected rheostat units 4a and So for independently adjusting the resistance in the circuits of the two oscillators.

By moving either one of the switch arms 35 down, the associated oscillator winding is connected in series with the battery I and the transmitter microphone 3 to form a complete operating circuit, whereby the transmitter microphone will supply current oscillations corresponding to sound impinging on the transmitter diaphragm to the actuating winding of the corresponding receiver for simplified operation without ampli- By moving either one of the switch arms 35 up, the receiver associated therewith will be connected in cascade through the associated amplifier microphone to the transmitter microphone 3 and the battery I, operating with currents supplied by the action of the transmitter microphone and amplified by the associated amplifier microphone.

Each receiver unit may be adjusted independently of the other unit either ior operation with a single circuit without the amplifier, or for.

operation with the amplifier. Both receivers may be operated over single circuits without amplification or over amplifying circuits with amplification. The arrangement provides also independent adjustment of the resistance of each receiver circuit to vary the ratio of the sound intensities of the two receivers, and both receivers have a common control of the total intensity for dif-. ferent operating conditions without substantially varying the ratio of the intensities of the two circuits.

By moving the switch arm 35 of the switch asosciated with the amplifier unit 2| to the downward position and the switch arm 35 of the amplifier 22 to the upward position, the following circuit connections will be obtained. From the battery terminal 9 through conductor 4], through contact 4|, contact member 38, through transmitter cord 6 by way of transmitter microphone electrodes I2, ll, through conductor 50, switch contacts 320 and 32a,.cord lead I including receiver 4 and rheostat- 4a, through switch contacts 33a, 330, through resistor 46, resistor rod 45, conductor 54, switch contacts 3411, 340, to the negative pole in of the battery. This con- .nects the receiver 3 with its individual rheostat 4a in series with the transmitter microphone 3 and the battery I, thus completing a single circuit. At the same time, the amplifier leads to the circuit are disconnected at the contacts 33b and 34b of the associated switch so that no current is diverted from the single circuit into the associated amplifier circuit. In the' same way, the receiver winding 15 of the bone receiver 5 may be connected to operate with a single circuit by pushing the contact arm 35 down, the same kind of a circuit being established as in case of the downward movement of the switch arm 35 of the switch associated with the other amplifier. I

On moving the, switch arm 35 controlling the connections of receiver 4 to the upper position, the following circuit connections are established. A primary circuit'extending from the battery pole 3 through conductor 41, by way of rheostat contact 4!, 38, 33, through cord 6 and the transmitter microphone electrodes I2, I I, to the amplifier winding 25 of amplifier 2i, and from the winding by way of switch contacts 341), 34a and conductor 48 to the negative pole ID of the battery. At the same time, a secondary circuit is established from the positive pole 3 of the battery, through conductor 41, rheostat contacts 33, resistor 31, conductor 53, switch contacts 32b, 32a, through the receiver winding l4, rheostat 4a, switch contacts 33a, 33b to the microphone chamber contact 23 of amplifier 2| to the diaphragm electrode 24, and therefrom through switch contacts 34b, 34a to the negative terminal ill of the battery.

The movable rheostat contacts 38 and 45 are mounted within the housing and are actuated in common so as to increase the resistance 43 in the simple receiver circuit simultaneously with the increase of the amount of the resistance of the resistor 40 included in the secondary amplifier circuit of the receiver. In this way the movement of a single button enables'control of the total intensity of the currents supplied to the two receivers irrespective of whether both receivers operate with single circuits, or one receiver operates with a single circuit and the other with an amplifier circuit, or both circuits operate with amplifying circuits. The independent control of the relative intensity of the sound produced by the air receiver 4 and the bone receiver 5, in addition to the common control of the total sound intensity produced by both oscillators is thus fully here secured over the full operating range with as well as without amplifiers.

the switch arm pended claims A distinct feature of the invention described in connection with Fig. 1 is the arrangement for easily changing the operation of a receiver unit from simple circuit operation to amplifying circuit operation without requiring removal or insertion of plugs or replacement of required in the prior art devices. The use of a simple switch with a single switch arm in com bination with an amplifier and a transmitter receiver and a battery as disclosed in connection with Fig. 1 enables a deafened person using only caring-aid a single receiver to easily adjust the to hear words spoken near to him by using the single circuit, as well as to instantly change the instrument for amplifier operation to enable him tohear speech from far away. No removal or insertion of parts of the device isrequired in changing from single circuit to an amplifying circuit operation. A simple movement. of the switch arm from one position to another converts the device from simplified to amplified operation, and vice versa.

Such hearing aid arrangements for operation with one receiver only are shown in Figs. 2 and 3.. In both arrangements the various connections of the single receiver; 4 with the transmitter 3, amplifier 2| and battery I are controlled by 35 to establish amplifier operating connections when the arm is in the inward position, and to establish simplified operating connections when the switch arm 35 is in its outward position. The rheostat' may be combined either with the amplifier housing 2 as shown in Fig. 2 or with the transmitter housing 3, as showninFig.3.

The invention is thus not limited to the details or specific locations of the elements of the hearing aid arrangements described in connection with the exemplifications shown in Figs. 1 to 3. It is accordingly desired that the apbe given a broad construction commensurate with the scope of the invention in the art.

It is claimed:

1.- In a wearable hearing aid device; a microphone transmitter unit; a receiver having a receiver actuating winding; a battery having two battery terminals; comprising an amplifier actuating winding, an amplifier microphone having two microphone electrodes, two amplifier supply terminals detachably engaging said battery terminals; one end of said amplifier to one of said amplifier supply terminals; cord a microphone amplifier unit.

cords as was 7 winding and one of said amplifier microphone electrodes being connected ically joining the same; portions of said cord leads forming parts of an input circuit interconnecting said battery and said amplifier winding' in series with said transmitter unit and parts of an output circuit interconnecting said amplifier winding with said receiver; and switching means embodied in one of said units and having circuit opening contact elements connected in said input and output circuits; said switching means including a movable member operative to actuate said contact elements between a position in which they complete said input circuit and said output circuit for supplying to 'said receiver amplified output currents corresponding to the input currents supplied to said microphone amplifier unit and a position in which said receiver is directly connected to said transmitter unit while said cord leads are maintained and extend in the same normal condition between said transmitter unit, said receiver and said amplifier unit.

2. In a wearable hearing aid device; a microphone'transmitter unit; a receiver having a receiver actuating winding; a battery having two battery terminals; a microphone amplifier unit comprising an amplifier actuating winding, an amplifier microphone having .two microphone electrodes, two amplifier supply terminals detachably engaging said battery terminals; one end of said amplifier winding and one of said amplifier microphone electrodes being connected to one of said amplifier supply terminals; cord leads extending between said amplifier unit, said transmitter unit and said receiver and mechanically joining the same; portions of said cord leads forming parts of an input circuit'interconnecting said battery and said amplifier winding in series with said transmitter unit and parts of an output circuit interconnecting said amplifier winding with said receiver; and switching means embodied in said amplifier-unit and having Ezecutria: of the Estate of Hugo Lieber, Deceased. 

